1. Technical Field of the Invention
The present invention relates to an audio network system that is capable of connecting a variety of audio devices.
2. Description of the Related Art
Conventional technologies for audio signal communication in a Professional Audio (PA) network system used for PA such as plays and concerts, music production, and private broadcasting include CobraNet (registered trademark) described in Non-Patent Reference 1, SuperMAC (registered trademark) described in Non-Patent Reference 2, and EtherSound (registered trademark) described in Non-Patent Reference 3.
[Non-Patent Reference 1]    http://www.balcom.co.jp/cobranet.htm
[Non-Patent Reference 2]    http://www.sonyoxford.co.uk/pub/supermac/
[Non-Patent Reference 3]    http://www.ethersound.com/news/getnews.php?enews_key=101
CobraNet is a professional audio network system developed by Peak Audio, Inc (USA). CobraNet provides a technology using the standard Ethernet (registered trademark) protocol of IEEE802.3u in which uncompressed audio signals and control signals of multiple channels are transmitted through the Ethernet. This technology can transmit audio data having a sample rate of 48 kHz and bit width of 16, 20, and 24 bits, and can handle the audio signals and control signals in two directions, each having up to 64 channels (i.e., up to 128 channels in both directions). SuperMAC and EtherSound are similar technology for transmitting audio signals over the Ethernet.
Audio devices having a variety of functions such as analog input, analog output, digital input, digital output, mixing, effecting, recording/reproducing, remote control, and a combination of any two of these functions can be optionally connected to an audio network that uses the above technologies.
In any method of the various technologies that have been developed for transmitting audio signals through the network as described above, the maximum number of channels for transmitting audio signals through the network is determined based on the transfer rate of the network. Accordingly, even though the conventional technologies are designed to allow any audio devices to be connected to the network, if all the transmission channels are already in full use, additionally connected audio devices cannot communicate audio signals. Thus, actually, the conventional technologies limit the number of connectable audio devices.
Further, although a console for controlling the audio devices is essential for the network connecting the audio devices, the conventional technologies have not taken into consideration a process for backup at the occurrence of a malfunction of the console. One may consider that, when a malfunction has occurred in the console, a new console is connected to the network as a substitute for the console. However, connecting the substitute console to the network may not be permitted due to the limitation on the number of audio devices.
In the various audio devices, often, their setting states are stored as scene data, and the scene is recalled to be set in the audio devices through a simple manipulation. However, when a structure connecting the various audio devices to a network as described above is employed, there is no choice but to individually store and recall scene data for each device, and it is also difficult and inconvenient to manage the scene data.